The objective of this proposed program will be to: (1) develop an innovative technology for fabrication and in situ characterization of planar artificial membranes and (2) implement this technology with an advanced surface-selective optical illumination technique for developing an ultra-sensitive Immuno-Sensor. The instrumentation includes the development of a new convection-free monolayer through with superior performance characteristics and optimized for characterization of lipid/protein monolayers at an air-water interface. Supported planar bilayers can be fabricated in the same through by utilizing a novel deposition mechanism. Bilayer deposition can be monitored by optical microscopy through-out the process. The experimental program will be directed towards gaining insight into the application of several advanced laser/optical-microscopic techniques for characterization of structure and function in lipid/protein membranes. Total Internal Reflection an advanced techniques for surface illumination will be utilized to probe the specific binding of IgG molecules to haptens in supported planar bilayers. The results of this highly sensitive approach will be used in developing an Immuno-Sensor. The successful completion of the proposed program will provide a highly useful diagnostics technology for a variety of biomedical applications such as: studying cell-cell recognition events, direct binding assays, fabrication of biocompatible materials, affinity chromatography and bio-specific sensors.